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United States Patent |
6,081,188
|
Kutlucinar
,   et al.
|
June 27, 2000
|
Vehicular hazard warning system
Abstract
An apparatus and method warn drivers of a hazardous condition experienced
by another driver. The apparatus generally includes a warning indicator,
such as for example a strobe light, coupled to a vehicle warning
controller. The vehicle warning controller is connected between a power
source and a plurality of vehicle detecting circuits which detect the
activation of a safety device. Vehicle detecting circuits can include an
antilock braking system (ABS) detecting circuit, an airbag deployment
detecting circuit, a rollover protection detecting circuit and an obstacle
detector detecting circuit. When at least one of the vehicle's detecting
circuits detects the activation of a safety device due to a hazardous
condition, a signal is sent to the vehicle warning controller. The warning
indicator is activated in response to a signal from the vehicle's warning
controller. Therefore, driver intervention is alleviated in warning other
motorists of potential danger.
Inventors:
|
Kutlucinar; Iskender V. (Kensington, MD);
Saul, II; Andrew M. (Chevy Chase, MD)
|
Assignee:
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Emergency Warning Systems, Inc. (Kensington, MD)
|
Appl. No.:
|
093189 |
Filed:
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June 8, 1998 |
Current U.S. Class: |
340/438; 340/471; 340/472 |
Intern'l Class: |
B60Q 001/00 |
Field of Search: |
340/438,463,468,471,472,479,903,440
|
References Cited
U.S. Patent Documents
5481243 | Jan., 1996 | Lurie et al. | 340/467.
|
5635922 | Jun., 1997 | Cho et al. | 340/903.
|
5760708 | Jun., 1998 | Seith | 340/973.
|
5828319 | Oct., 1998 | Tonkin et al. | 340/964.
|
Primary Examiner: Lefkowitz; Edward
Attorney, Agent or Firm: Kenyon & Kenyon
Claims
What is claimed is:
1. A vehicular hazard warning system comprising:
(a) at least one sensor being triggered by an event and producing a signal;
(b) at least one controller for receiving said signal and determining
whether to activate a vehicle safety device;
(c) at least one detecting circuit which detects activation of a vehicle
safety device by said controller; and
(d) at least one hazard warning indicator which is detectable externally to
a vehicle containing the warning system, said hazard warning indicator
being activated in response to the detected activation of said safety
device.
2. The vehicular warning system according to claim 1, wherein said at least
one warning indicator is a light or auditory signal.
3. The vehicular warning system according to claim 2, wherein said at least
one warning indicator is a horn.
4. The vehicular warning system according to claim 2, wherein said at least
one warning indicator is a high intensity light.
5. The vehicular warning system according to claim 1 comprising a plurality
of said detection circuits.
6. The vehicular warning system according to claim 1, wherein said at least
one detecting circuit is an antilock brake deployment detecting circuit.
7. The vehicular warning system according to claim 1, wherein said at least
one detecting circuit is an airbag deployment detecting circuit.
8. The vehicular warning system according to claim 1, wherein said at least
one detecting circuit is a rollover protection activation detecting
circuit.
9. The vehicular warning system according to claim 1, wherein said at least
one detecting circuit is an obstacle detector detecting circuit.
10. A vehicle having a vehicular hazard warning system comprising:
(a) at least one sensor being triggered by an event and producing a signal;
(b) at least one controller for receiving said signal and determining
whether to activate a vehicle safety device;
(c) at least one detecting circuit which detects activation of a vehicle
safety device by said controller; and
(d) at least one hazard warning indicator which is detectable externally to
a vehicle containing the warning system, said hazard warning indicator
being activated in response to the detected activation of said safety
device.
11. A method for activating a vehicular hazard warning system comprising
the steps:
(a) detecting a hazardous condition;
(b) communicating the detected hazardous condition to a control unit;
(c) determining whether the hazardous condition exceeds a predetermined
threshold;
(d) activating at least one safety device if potentially hazardous
condition exceeds the predetermined threshold;
(e) monitoring said control unit for activation of said vehicle safety
device (f) detecting activation of said safety device; and
(g) activating said warning hazard system in response to the detected
activation of said safety device.
12. The method for activating a hazard warning system according to claim
11, wherein the step of activating said warning hazard system comprises
illuminating a light or sounding an auditory signal or both.
13. The method for activating a hazard warning system according to claim
11, wherein the step of activating said warning hazard system comprises
sounding a horn.
14. The method for activating a hazard warning system according to claim
11, wherein the step of activating said warning hazard system comprises
illuminating a light.
15. The method for activating a hazard warning system according to claim
14, wherein the light is a high intensity light.
16. The method for activating a hazard warning system ac cording to claim
11, wherein the step of detecting the activation of a safety device
comprises detecting activation of an antilock braking system .
17. The method for activating a hazard warning system according to claim
11, wherein the step of detecting the activation of a safety device
comprises detecting activation deployment of an airbag or airbags.
18. The method for activating a hazard warning system according to claim
11, wherein the step of detecting the activation of a safety device
comprises detecting activation of a rollover protection system.
19. The method for activating a hazard warning system according to claim
11, wherein the step of detecting the activation of a safety device
comprises detecting the presence of an obstacle.
20. The method for activating a hazard warning system according to claim
11, further comprising the step of reset ting said hazard warning system.
21. A vehicular hazard warning system comprising:
(a) at least one sensor being triggered by detecting a hazardous driving
condition and producing a signal;
(b) at least one controller for receiving said signal;
(c) at least one detecting circuit which receives an indication from said
controller of a hazardous driving condition;
(d) at least one hazard warning indicator which is detectable externally to
a vehicle containing the warning system, said hazard warning indicator
being activated in response to an indication from said at least one
detecting circuit.
Description
FIELD OF THE INVENTION
The present invention relates to the field of motor vehicles. More
particularly, the present invention is directed to a system that provides
a warning to others of the possibility of a hazard experienced by a driver
of a vehicle in which the warning system is installed.
BACKGROUND
Prior art vehicular warning light systems commonly include a taillight
assembly, headlight assembly, brake light assembly, turn signal assembly,
and an emergency flasher assembly, all employing incandescent light bulbs.
Each of these assemblies operates in a well-known manner to illuminate the
roadway, to indicate an impending stop or slowdown, indicate an impending
turn, or indicate an emergency condition of some nature.
Conventional vehicular warning lighting systems suffer from certain
drawbacks under modern driving conditions. For example, emergency
flashers, which are standard equipment on motor vehicles, require that a
vehicle occupant operate the flashers by pressing a switch that is usually
located on or near a vehicle's steering column. Typically, these flashers
are employed by the driver when the driver is in a distressful situation
or to warn others including other drivers, of the vehicle's presence.
Therefore, if the driver or other occupant cannot activate the flashers,
other drivers will not become aware of a driver's peril or the vehicle's
presence.
Another conventional vehicular warning lighting system is the use of brake
lights. The driver must apply the brakes in order to activate this warning
device to alert others of a potential hazard. Even if the driver does
activate the system, occasions can arise where there is still insufficient
warning to others. For example, in the situation where a leading vehicle
applies a conventional brake light system used to indicate that the
vehicle is slowing down or stopping, a following vehicle may not have
sufficient time to stop because the following vehicle may be located too
close to the leading vehicle such that the brake lights of the leading
vehicle cannot be seen in sufficient time to allow the following vehicle
to stop. Additionally, on very sunny days, the intensity of the brake
lights is such that a driver may not be able to determine whether the
brakes have been applied in the leading vehicle.
Other forms of vehicular warning systems include horns, flares or a white
flag or towel displayed on the vehicle to indicate that the driver is in
distress. In each of these cases, however, these warning systems require
driver intervention.
Therefore, it can be appreciated that there exists a need for a vehicular
warning system which indicates to others that a vehicle or its occupants
are experiencing a hazardous condition or are in a dangerous position, but
which does not require any intervention from the driver of that vehicle.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in known types of prior art
vehicular warning systems, the present invention provides a vehicular
warning system, which detects when the automobile in which it is employed
has engaged a safety mechanism or is in a hazardous condition and provides
an appropriate warning to others about the condition.
To attain this, the vehicular warning system of the present invention
generally comprises at least one warning indicator which is detectable
outside of the car in which the system is installed, such as a light or an
audible indictor which is operationally coupled to a warning controller.
Examples of a light indicator include a strobe light, or other high
intensity light. The audible indicator could be a horn. The warning
controller, which is preferably a microprocessor, is operationally coupled
to a power source and a detecting circuit(s) which detects the activation
of a vehicle safety device or detects a hazardous condition with regard to
the vehicle in which the warning system is installed. Examples of
hazardous conditions include the vehicle reaching its maximum braking
capacity and the wheels locking up, the vehicle experiencing frontal or
side impact, the vehicle positioned too close to an obstacle such as
another vehicle, a pedestrian, etc., the vehicle tilting over and other
similar situations. Examples of detecting circuits include an antilock
braking system (ABS) detecting circuit, an airbag deployment detecting
circuit, a rollover protection detecting circuit and a parking aid
detecting circuit. Upon activation of at least one of the abovementioned
vehicle safety devices, a signal from an associated detecting circuit(s)
is provided to the vehicle warning controller. The vehicular warning
system is activated in response to a signal or signals from the vehicle
warning controller. Upon detection of the signal, the warning indicator is
automatically engaged so that there is no need for driver intervention.
It is to be understood that the invention is not limited in its application
to the details of construction and arrangements of the components set
forth in the following description or illustrated in the drawings. The
invention is capable of other embodiments and of being practiced and
carried out in various ways. Also, it is to be understood that the
phraseology and terminology employed herein are for the purpose of
description and should not be regarded as limiting.
The term "vehicle" as used herein includes, but is not limited to, all
types of motorized transportation including automobiles, trucks, vans,
motorcycles and the like. The term "automatically" is used herein to mean
that the system is activated without human intervention.
As such, those skilled in the art will appreciate that the invention, upon
which this disclosure is based, may readily be utilized as a basis to
design other structures, methods and systems for carrying out the purpose
of the present invention. It is important, therefore, that the claims are
regarded as including such equivalent construction insofar as they do not
depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood when consideration is given to the
following detailed description thereof. Such description makes reference
to the annexed drawings wherein similar reference characters refer to
similar parts throughout the several views of the drawings:
FIG. 1 is a block diagram depicting the functional interrelationships of
the components of the vehicular warning system of the present invention.
FIG. 2 is a block diagram depicting the functional interrelationships of
the components of an airbag system and the vehicular warning system of the
present invention.
FIG. 3 is a block diagram depicting the functional interrelationships of
the components of a rollover protection system and the vehicular warning
system of the present invention.
FIG. 4 is a block diagram depicting the functional interrelationships of
the components of an obstacle detection system and the vehicular warning
system of the present invention.
FIG. 5 is a block diagram depicting the functional interrelationships of
the components of an antilock braking system (ABS) and the vehicular
warning system of the present invention.
DETAILED DESCRIPTION
The present invention is a vehicle warning system for alerting drivers that
the vehicle containing the vehicle warning system is experiencing
dangerous or potentially dangerous conditions or is in a hazardous
position. The vehicle warning system of this invention preferably includes
at least one detecting circuit to detect activation of at least one safety
device within the vehicle or to detect a hazardous road condition. In the
alternative and as shown if FIG. 1 a plurality of detecting circuits may
be used, each connected to an electronic control unit (ECU) of a vehicular
safety device. According to one aspect of the present invention, each of
the detecting circuits may be used independently of one another. The
detecting circuits which may be employed with the present invention
include an (ABS) activation detecting circuit, an airbag deployment
detecting circuit, a rollover protection system activation detecting
circuit and an obstacle detection detecting circuit, although it will be
appreciated that the vehicular warning system of the present invention may
be used in conjunction with any vehicle safety device concurrently
installed in the vehicle. Referring to FIG. 1, each of the detecting
circuits (5-8) is connected between an ECU for each of the safety devices
and a vehicle warning controller 100. In particular, detecting circuit 5
is connected between airbag system ECU 10 and warning controller 100.
Detecting circuit 6 is connected between rollover protection system ECU 20
and warning controller 100. Detecting circuit 7 is connected between
obstacle detection system ECU 30 and warning controller 100. Detecting
circuit 8 is connected between ABS system 40 and warning controller 100.
Each of the above-mentioned detecting circuits receives a signal from its
respective ECU, indicating the activation of the corresponding safety
device. Various signaling methods can be employed to communicate to the
detecting circuits that a safety device has been triggered. Such a
signaling method may include the generation of an electrical or optical
pulse by the ECU such that the detecting circuit is notified when a safety
device has been activated. While the respective detecting circuits have
been illustrated as discrete elements, they could, alternatively, be
provided in an integrated design.
The output of each of the detecting circuits is provided to a vehicle
warning controller 100 which in turn is functionally connected to a power
supply 101 and a warning indicator 200. Alternatively, a plurality of
warning controllers 100 may be employed. Warning indicator 200 may
include, for example, a light such as a high-intensity light or a horn, or
a combination of such devices. Electrical power is provided by a
conventional storage battery, solar battery or other power source 101
supplemented as necessary by a conventional electrical generating system
(not shown). Each of the detecting circuits continuously monitors its
respective ECU and emits an alarm signal to the warning controller 100
when its respective ECU indicates that a safety device has been activated.
Warning controller 100 then activates warning indicator 200 which
transmits a warning signal that a hazardous condition has been detected.
The warning signal can remain activated until a predetermined time has
expired. Alternatively, the warning signal can be terminated automatically
or manually by the vehicle occupant.
According to FIG. 1 and the principles of the present invention, hazardous
conditions are detected (acknowledged) by sensors (1-4). Sensors (1-4) may
include, but are not limited to, short-circuiting ring sensors, ultrasonic
sensors, solenoid plunger sensors, optical sensors, etc. Sensors (1-4)
represent a peripheral communications link between a vehicle and the ECU
used for processing. Sensors (1-4) convert physical quantities such as the
external force applied to the body of a vehicle into an electrical
quantity adapted to communicate with a processing device such as an ECU.
Examples of such sensors include, but are not limited to, fiberoptic
sensors, inductive sensors, gradient sensors, tangential senors, radar
sensors, piezoelectric sensors, and the like.
The entire device as shown in FIG. 1 may be mounted within a small cabinet
and secured beneath the dashboard of an existing vehicle. Alternatively,
the present invention may be incorporated as original equipment in an
automobile or other types of vehicle and may be mounted in any convenient
location therein.
The following is a description of the various implementations of the
vehicular warning system used with the systems of the present invention.
System For Detecting Airbag System Deployment
An airbag system is a vehicular occupant protective system designed to
protect a vehicular occupant in case of a vehicle collision. An airbag
system generally includes a sensor for detecting a vehicle collision, an
inflator for releasing gas into an airbag when a signal is received from
the sensor and an airbag that inflates with gas released from the
inflator. When a vehicle experiences a collision, the airbag inflates
between the vehicular occupant and interior components of the vehicle,
such as a dashboard or a steering wheel located in front of the vehicular
occupant.
FIG. 2 illustrates an airbag system which may be used with a warning
controller 100 in accordance with an embodiment of the present invention
to alert other drivers that an airbag has deployed in the car carrying the
warning system. It will be understood that the airbag system as well as
the following safety systems are only exemplary, and many other safety
systems are available to those skilled in the art to accomplish
substantially the same results. As shown in FIG. 2, a front-passenger
airbag 21 and a driver airbag 22 are deployed from the dashboard area 23
of a vehicle. Also included is seatbelt tightener 24, which is used to
restrain the occupant when the airbags deploy and sensor 1, which is used
to detect that the vehicle is in a hazardous situation. Once sensor 1
detects an external pressure exerted on the vehicle, a signal is sent from
sensor 1 to ECU 10. ECU evaluates the information supplied by sensor 1 and
determines whether to deploy airbags 21 and 22. If ECU 10 determines that
the airbags require deployment, ECU 10 generates a signal to activate the
airbags. From the signal sent to activate the airbags, detecting circuit 5
determines, (via an electrical pulse or the absence of an electrical
pulse, for example), that the airbag(s) has been deployed and communicates
this information to warning controller 100.
Upon vehicle collision, a pyrotechnic gas generator inflates (not shown)
airbags 21 and 22 in a sudden, explosive process designed to ensure
complete inflation prior to occupant contact. The airbags then respond to
occupant contact with partial deflation in a response pattern calculated
to combine "gentle" force absorption with physiologically acceptable
surface pressure and decelerative forces for the occupant. This prevents,
or at least greatly reduces, the probability of severity of head and chest
injuries to the passenger and/or driver.
Separate airbags for the driver and front seat passenger protect against
head and front injuries stemming from impact about less than 60 km/h
against a solid obstacle. Airbags 21 and 22 also protect occupants who are
not wearing seatbelts, and are therefore of particular benefit in areas or
regions where seatbelt use is not mandatory.
The gas generator inflates the full-sized driver airbags 22 with nitrogen
(N.sub.2) (volume approximately 50 to 60 liters) in 30 to 35 ms, while
roughly 50 ms are required to fill the full-sized frontal passenger airbag
21 where the volume is approximately 100 to 140 liters installed in the
glove compartment area.
The seatbelt tightener 24 compensates for belt slack and the film-reel
effect by retracting (tightening the belts) to further enhance the
protection afforded by automatic seatbelts. Seatbelt tightener 24 also
includes buckle tightener 25. Buckle tightener 25 pulls the seatbelt
buckle rearward to simultaneously tighten the shoulder and lap belts.
Buckle tightener 25 combines improved restraint with enhanced protection
against "submarining" (in which occupants slide forward beneath the lap
belts). A prerequisite for optimum protection is that the occupants'
forward movement away from their seats remain minimal as they decelerate
along with the vehicle. This is achieved by triggering seatbelt tightener
24 immediately upon initial impact to ensure that effective restraint
starts as soon as possible. The maximum forward displacement with
tightened seatbelts is approximately 1 cm and the duration of mechanical
tensioning process is approximately 5 ms to a maximum of 12 ms. Although
seatbelt tightner 24 is used to further enhance the safety of the
occupants, the system for detecting airbag deployment can be activated
without the use of seatbelt tightner 24.
Of decisive importance to the safety of passengers is to trigger the
process of releasing/inflating airbags at precisely the right instant. The
occupants contact the airbag at the instant in which it is fully inflated
and just starting to deflate. Maximum forward displacement on the driver's
side is usually defined at 12.5 cm (the "5 inches rules") with airbag
deflation times of approximately 100 ms. The entire impact and energy
absorption process is therefore completed within approximately 150 ms.
Moreover, as soon as this process has been triggered, information about
the airbag's deployment is communicated to warning controller 100. Warning
controller 100 then sends a signal to warning indicator 200 which
activates a light or horn or other warning signal or device to alert other
drivers of a hazardous condition. Generally, the warning signal can be
adjusted to be detected at a distance of up to 1 mile and can be adjusted
to be detected from the air or the road. Moreover, the warning system can
be adjusted to distinguish between conventional vehicle audible or
lighting systems. For example, strobe lights or other high-intensity
lights can be used.
System For Detecting Rollover Protection System Deployment
A rollover protection system is a vehicular occupant protective system
designed to protect a vehicular occupant in the event that the vehicle
overturns. Many modern day sports cars and convertibles, particularly of
the two-seat configuration, have a rollover bar that extends across the
passenger compartment just behind the seat structure for safety reasons.
In vehicles with demand-deployment rollover bars and rear head restraints
an electronic triggering unit (rollover sensor) provides substantially
instantaneous protection in response to incipient vehicle roll by
triggering a powerful solenoid to release a pre-tensioned activation
spring. Therefore, rollover bars protect occupants from severe injury when
the vehicle overturns.
Referring now to FIG. 3, a convertible vehicle 31 is shown with a rollover
protection system. A roll bar 33 is pivotally mounted in the center of the
vehicle. The roll bar 33 has a generally inverted U-shaped configuration
with side leg portions 32 and 34 extending downward from the elongated
upper or top portions thereof to a pivotal mounting assembly 35 which
includes a main support bar 36.
The main support bar 36 is mounted in a suitable manner such as by a
bracket or the like at each end thereof, securing the support bar 36
directly to a side wall panel in the interior of the vehicle's body.
Because vehicle roll can be characterized by deviations from the
horizontal plane in any direction--both linear and lateral--the rollover
sensors are able to monitor an extended range of vehicle attitudes.
Referring to FIG. 3, rollover sensor 2 is coupled to mounting assembly 35.
Mounting assembly 35 communicates with rollover sensor 2 to inform the
sensor of the position of the vehicle. If the mounting assembly
communicates to rollover sensor 2 a value that exceeds or falls below a
predetermined value for describing the position of the vehicle, rollover
sensor communicates this information to ECU 20. ECU 20 then determines
whether to activate the rollover protection system. Once ECU 20 determines
that the rollover protection system should be activated, detecting circuit
6 detects activation of the protection system and immediately forwards the
information to warning controller 100. Warning controller 100 then sends a
signal to warning indictor 200 which alerts other drivers of a hazardous
condition. Rollover sensor 2 is also coupled to an external sensor (not
shown) to determine the position of the car with respect to the ground and
the speedometer (not shown) to determine the speed of the vehicle.
Data employed by rollover sensor 2 to detect an impending roll, includes
the vehicle's acceleration and tilt angles as well as extension rates at
the rear suspension and loss of contact between the vehicle and the road
surface. Separate acceleration sensors for the longitudinal and lateral
planes monitor vehicular acceleration in all directions. A microcomputer
located in ECU 20 squares and sums the sensor signals before comparing the
resulting acceleration data with the programmed activation threshold of
roughly 5 g (where g is the acceleration of a freely falling object). A
tilt switch evaluates the vehicle tilt as a second triggering criterion.
The system also deploys the rollover bar 36 if vehicle inclination reaches
more than 27 degrees and at least one of the two rear-axle switches has
opened to generate a signal indicating rear-wheel rebound. The
microcomputer and an analog hardware path furnish redundant verification
of the second triggering condition in order to increase operating safety.
As well as the triggering functions, the rollover sensor 2 also carries out
self-diagnosis, in which the external actuators, the rear-suspension
switches, electrical system voltage and the warning lamp are diagnosed. It
has a non-volatile memory, a fault clock and a serial diagnostic
interface. The system responds to activation conditions by releasing the
central locking system. Other lateral roll-detection systems employ tilt
sensors to determine the vehicle's angular inclination (where the roll
angle is greater than 52 degrees and the pitch angle is greater than or
equal to 72 degrees). Another alternative is to use a gravity sensor
designed to respond to the loss of road contact characteristic of
incipient rollover by closing a spring-loaded Reed contact. As soon as
rollover sensor 2 detects that the vehicle exceeds a predetermined
vehicular angular inclination, this information is communicated to warning
controller 100. Warning controller 100 then sends a signal to warning
indicator 200 which activates a light or horn or other warning signal or
device to alert other drivers of a hazardous condition.
A System For Detecting Obstacles With Ultrasonic Sensors:
The obstacle detector system of the invention functions to determine the
distance of a vehicle from an obstacle and to warn other vehicles if a
dangerous condition is detected. The term "obstacle" is used herein to
mean a stationary or moving object within the path of the sensor, such as
for example, vehicles, pedestrians, etc. The system includes at least one
ultrasonic sensor and an evaluation circuit to determine the distance of
the vehicle from an obstacle. Referring to FIG. 4, a block diagram of a
circuit arrangement for the obstacle detector system is shown. Ultrasonic
sensor 41 transmits sound waves and measures the transmitted time of an
echo reflected from an obstacle. In this arrangement, the measurement of
the distance from the obstacle is sufficiently precise during the approach
to an obstacle as far as to a specific minimum value. The ultrasonic
sensor(s) can be located under or on the front and/or rear bumpers of the
vehicle. In the alternative, ultrasonic sensors can be located in any area
which is useful for detecting the presence of an obstacle when the vehicle
is traveling at various speeds and in various directions.
The block diagram of FIG. 4 illustrates ECU 30, which has a microprocessor
45 with a program memory 46. Contained in the program memory 46 is a
control program used for measured value registration and evaluation. Also
included in ECU 30 and functionally connected to microprocessor 45 is a
system activation indicator 44. System activation indicator 44 may be for
example, an output port which is used to determine whether the system has
been activated. The microprocessor 45 is functionally connected to a
display 47, on which the distance values are displayed so that the driver
or passenger may detect the display. Microcomputer 45 is also connected on
the input side to one or more ultrasonic sensors 3. The functions of
microprocessor 45 include triggering the abovementioned components and
monitoring any defects discovered in the system.
Sensors 3 are in the form of a housing such as an aluminum housing
optionally having selective damping, a piezoelectric wafer as a wave
generator, and the electronic circuitry necessary for the generation of
ultrasonic waves and evaluation of reflected, received waves. In an
alternative embodiment, sensors 3 may be already provided with the use of
another system, such as for example, the ABS or the rollover protection
system.
The obstacle detecting system can become activated only when the ignition
is switched on, and the transmission engaged. Operation generally starts
with an initial self-test in which display 41 and sensors 3 are activated
and checked for correct operation. Upon completion of the self-test, the
system indicates correct functioning either by means of a "ready" display
or by indicating the distance to an obstacle. If a fault is detected (for
instance a cable breaks), a warning tone or light or other signal is
switched on for about 3 seconds. The driver is informed of the system
status either optically or audibly or both, and has the option of
switching off the system by means of a switch (not shown) if circumstances
demand. This can be the case for instance in "stop-and-go" traffic at
speeds below 15 km/h.
While driving, the sensors are triggered approximately every 50 ms,
preferably every 40 ms and most preferably every 25 ms and generate an
ultrasonic pulse of about 1-5 ms, preferably about 1 ms. The sensors 3
then switch to "listen" so that they can receive reflected waves. The
distance to an obstacle from which the waves are reflected is calculated
by processing the transmitted time taken for the waves to travel from the
transmitting sensor to the receiving sensor. The shortest distance in each
case from the obstacle to the bumper is optionally indicated to the driver
on display 47.
The system may be programmed to detect obstacles which are a predetermined
distance away from the vehicle at a given speed or the system can be
automatically set to detect obstacles at a predetermined distance without
driver intervention. For example the system may be programmed to detect an
obstacle at 15 feet at 25 mph or 40 feet at 65 mph. Sensor(s) 3 are used
to determine the position of the vehicle in respect to a detected
obstacle. The sensors communicate this information to microprocessor 45
which alerts the obstacle system that an obstacle is within the
predetermined or programmed range. Once microprocessor 45 determines that
an obstacle is too close to the vehicle and the vehicle has not
decelerated, microprocessor 45 communicates with display 47 to alert the
driver of a potentially hazardous situation. Detecting circuit 7 detects
that the obstacle system has been activated and forwards this information
to warning controller 100. The warning controller 100 signals warning
indicator 200 to warn others of a potential hazard. System For Detecting
(ABS) Antilock Braking System Deployment:
Antilock braking systems (ABS) are closed loop control devices within the
braking system which prevent wheel lock up during braking and, as a
result, retain the vehicle's steerability and stability. The main
components of ABS are a hydraulic module, wheel-speed sensors, and a
microprocessor for signal processing and control of actuators in the
hydraulic modular.
Upon initial braking, brake pressure is increased; the brake slip increases
and at a maximum point on an adhesion/slip curve, the brake slip reaches a
limit between a stable and unstable range. From this point on, any further
increase in the brake pressure or braking torque does not result in a
further increase in the braking force. In the stable range, the brake slip
is largely the result of a deformation slip. The brake slip increasingly
tends toward skidding in the unstable range.
Referring now to FIG. 5, one example of an ABS control system that can be
used with the present invention is shown. The ABS control system generally
includes a solenoid-valve unit 51, master cylinder 52, a wheel brake
cylinder 53, an electronic control unit 40 including a microprocessor 56
and a wheel speed sensor 4. Wheel-speed sensor 4 monitors the motion of
the wheel 58. If one wheel shows signs of locking, there is a sharp rise
in peripheral wheel deceleration and in wheel slip. If these exceed
defined critical conditions, the ECU 40 sends a command to solenoid-valve
unit 51 to stop or to reduce the buildup of wheel-bake pressure until the
danger of lock up has passed. The brake pressure must then be built up
again in order to ensure that the wheel is not under braked. During
automatic brake control, it is constantly necessary for the stability or
instability of the wheel motion to be detected, and the wheel must be kept
in the slip range with maximum braking force by a succession of
pressure-buildup, pressure-reduction and pressure-holding phases. When the
ABS system is activated, ECU 40 forwards a signal to microprocessor 56
that automatic braking control is being employed. Detecting circuit 8
detects the signal sent to microprocessor 56 and alerts warning controller
100 that the ABS system has been activated. Warning controller 100 then
notifies warning indicator 200 that the vehicle may be experiencing a
hazardous condition. Warning indicator 200 is then activated.
Alternative Subsystems Deployable With Warning Control:
Another example of a subsystem that can be included (either alternatively
or collectively) with the vehicular warning system include, for example,
is a vehicle dynamic system. Vehicle dynamics is defined herein as the
overall behavior of the entire system represented by "driver +vehicle
+environment". As the first link in the chain, the driver makes judgements
on vehicle operating behavior based on the sum of various subjective
impressions. Meanwhile, data on operating behavior, based on specific
driving maneuvers executed without driver input ("open-loop operation")
provide an objective description of the vehicle's operating response.
Since the driver's driving behavior cannot be precisely defined, testing
and/or warning systems of the present invention replace the driver input
with a specific, objectively quantifiable interference factor. The
resulting vehicular response is then analyzed and an appropriate response
made.
Standardized versions of the driving maneuvers in the list (performed on a
dry road surface) below have already either been defined or are under
consideration; they serve as recognized standard procedures for vehicular
evaluation:
Steady-state skidpad,
Transient response,
Braking during cornering,
Crosswind sensitivity,
Straight-running stability, and
Reaction to throttle change on skidpad.
To date, it has still not been possible to arrive at comprehensive
objective definitions for the dynamic characteristics associated with
closed-loop operation, as adequate data on the precise control
characteristics of the human element are still unavailable.
The main criteria employed in evaluating vehicle dynamics are:
Steering-wheel angle,
Lateral acceleration,
Longitudinal acceleration and deceleration,
Yaw speed,
Float and roll angles.
Additional data are employed to verify and confirm the previously derived
information on specific points of vehicle performance:
Linear and lateral velocity,
Steering angles at front and rear wheels,
Slip angles at all wheels,
Camber and pitch angles,
Steering-wheel force.
A detecting circuit can be employed to detect and monitor the operation of
any of these features alone or in combination. The detecting circuit can
be connected to warning controller 100 to indicate activation of one or
more of the above-mentioned safety devices.
There has thus been shown and described a novel system for automatically
warning others of hazardous conditions experienced by the driver of a
vehicle in which the system is installed. Many changes, modifications,
variations and other uses and applications of the subject invention, will
however, become apparent to those skilled in the art after considering
this specification and the accompanying drawings which disclose the
preferred embodiments thereof. All such changes, modifications, variations
and other uses and applications which do not depart from the spirit and
scope of the invention are deemed to be covered by the invention which is
limited only by the following claims.
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